Turning the Hexbug spider into a line-following robot

You may be familiar with the Hexbug Spider, a small electronic robot toy sold at Target and Walmart for $20. While they’re able to be commanded to move forward, backward, and spin around on a dime, there aren’t any external sensors to make it really exciting. [Eric] sought to remedy this and came up with a line-following board replacement for the Hexbug Spider.

The stock Spider has a small circuit board that allows for the control of two motors with a remote. [Eric] removed this control board and replaced it with his own, powered by a TI MSP430 microcontroller. On this board, [Eric] included a pair of IR LEDs, able to detect the path of a white line drawn on the ground. With just a little bit of code, [Eric] made his $20 Hexbug Spider into a very cool looking robot.

[Eric] figured out how to improve his robot toy, but the power of the MSP430 microcontroller he used doesn’t limit him to only following lines. By using an MSP430 Launchpad, anyone can upload new code to the improved Spider, and even add new sensors to this creepy walking robotic toy.

The design is (afaik, although I bet Hexbug would claim otherwise) by a guy called Jaimie Mantzel – check around on his Youtube channel -http://www.youtube.com/user/JMEMantzel/featured –
one of his (many) videos shows how it works.
HexBug got hold of it after he sent a demo unit to various toy companies to find someone to produce it, and they decided they could get a better deal by cutting him out (more-or-less).

It seems to waste time repeatedly scanning in the wrong direction when following curves. Changing the code slightly to scan in the direction of the previous successful acquisition would probably speed up cornering a bit.